Using Pneumatics

I’m just clarifying now. Pneumatics DO NOT count into my 10 motor limit, correct? I can’t see why they would, but I just felt like making 100% sure before buying the kits and stuff I’m going to need.

Secondly, how do I program a Pneumatic? I’m using EasyC, which means it’s probably just a tile that I’m not finding.

Third, I cannot find a limit on the number of pneumatics I can use on my robot. Or a limit to the number of air cylinders. Is there one I’m missing in the Manual?

Thanks to anyone who can answer my questions.

  1. Correct.
  2. Programming Pneumatics is very easy. Basically you have 0’s and 1’s. With easyC, I bet there will be a button saying activate piston, deactivate.
  3. There is no limit to number of pistons/tanks on a robot.

Hope this helps!

Robert

Sounds perfect. But I was planning to use Pneumatics with a button on the Joysticks. Same procedure? Just look for a pneumatic block? Or is there a something I’m missing?

  1. Pneumatics definitely do NOT count towards the 10 motor limit, so you’re fine there.

  2. I use ROBOTC, but as far as I’m concerned programming them should just involve sending an off or on signal to the solenoid sensor that connects to a piston). In ROBOTC, solenoids are set as “digital out” sensors and are set to either 0 or 1 in the code to determine whether they should extend or retract. I’m sure someone else here could help you with EasyC.

  3. We used pneumatics on our Gateway robot, and after reading the manual and doing research we couldn’t find any limit to the number of pistons or air cylinders. I’m 99% sure you can use as many as you can fit onto your robot (or as many as you can afford to purchase).

I’m assuming you are using V4, look for the “SetDigitalOutput” block. In order to program it, it is as simple as: (This will be ugly but it is just a quick representation)


IF ( Button1 == Pressed ) 
{
     SetDigitalOutput = 1 // either 1 or 0
}
IF ( Button2 == Pressed ) 
{
     SetDigitalOutput = 1 // either 1 or 0
}

This was a very quickly written section of code. If it doesn’t make sense let me know.

Only real limit for pneumatics outside of the ports to fire the solenoids is the cost of components and how much physical space the air tanks occupy in the starting configuration dimensions.

Just make sure you design around the number of times you can actuate your cylinder complement based on your onboard storage and should be fine.

@Dpbailey- That makes perfect sense, thanks.

@Phyrxes- I’m just using the pneumatics to move a small piece a few centimeters, mostly because I’m already at 10 motors. I should be fine on keeping the cylinders charged, and for the design we’ve drawn up I can just stick the cylinders on the side of the lift. Unless I need to protect them, I guess, in which case I would just mount them on the base and use more tubing.

Anytime! :smiley:

Does anyone think that the pneumatics only can lift a bucket all the way to the trough?

dontworryaboutit made a great post on this recently:

This is based on the assumption that a piston can lift 12lb.

It’s very possible though using elastic assistance via elastic tubing or rubber bands. Check out the DiscoBots robot from Gateway: https://vimeo.com/40536229 (Look ~0:40 seconds for the pneumatic cylinders raising and lowering their arm)

They used pneumatics to raise and lower their arm, allowing them to have more motors on their drive. How well it actually performed, I’m not sure - but it’s definitely not par for the course in VEX, so I think it’s pretty cool.

Your able to use multiple selenoids and buttons on the controller to control as many pneumatic pumps as you want. There is no limit, which can be an advantage AND a disadvantage. The more pumps you use (depending on how many you plan to use) you will add more weight, including the tanks. So use them wisely, but it sounds you’re only buying one kit so that won’t be a problem. Good luck with them they’re the best thing for our robots in the past years :slight_smile:

Our arm worked very well. We used two double action pistons, one on each arm. We used a massive amount of latex on each arm (20-35 feet??). The arm was tensioned so that it favored the middle of its range of motion.

If I did it again I would use >2 single action pistons to raise the arm up and 1 single regulated to a lower power + gravity to bring it down. This would conserve air.

In our case it was very important to keep the latex fresh.

Wasabi had a very cool multi stage pneumatic arm. Ours passively adapted between the medium and high goals.